Exercise and diet modification in non-obese non-alcoholic fatty liver disease: analysis of biopsies of living liver donors

A Worldwide Survey of Live Liver Donor Selection Policies at 24 Centers With a Combined Experience of 19 009 Adult Living Donor Liver Transplants

BACKGROUND

Although surgical technique in living donor liver transplantation (LDLT) has evolved with a focus on donor safety and recipient challenges, the donor selection criteria remain considerably disparate.

METHODS

A questionnaire on donor selection was sent to 41 centers worldwide. 24 centers with a combined experience of 19 009 LDLTs responded.

RESULTS

Centers were categorized into predominantly LDLT (18) or deceased donor liver transplantation (6), and high- (10) or low-volume (14) centers. At most centers, the minimum acceptable graft-to-recipient weight ratio was 0.7 or less (67%), and remnant was 30% (75%). The median upper limit of donor age was 60 years and body mass index of 33 kg/m. At 63% centers, age influenced the upper limit of body mass index inversely. Majority preferred aspartate transaminase and alanine transaminase less than 50 IU/mL. Most accepted donors with nondebilitating mild mental or physical disability and rejected donors with treated coronary artery disease, cerebrovascular accident and nonbrain, nonskin primary malignancies. Opinions were divided about previous psychiatric illness, substance abuse and abdominal surgery. Most performed selective liver biopsy, commonly for steatosis, raised transaminases and 1 or more features of metabolic syndrome. On biopsy, all considered macrovesicular and 50% considered microvesicular steatosis important. Nearly all (92%) rejected donors for early fibrosis, and minority for nonspecific granuloma or mild inflammation. Most anatomical anomalies except portal vein type D/E were acceptable at high-volume centers. There was no standard policy for preoperative or peroperative cholangiogram.

CONCLUSIONS

This first large live liver donor survey provides insight into donor selection practices that may aid standardization between centers, with potential expansion of the donor pool without compromising safety.

The Effects of Physical Exercise on Fatty Liver Disease

The increasing prevalence of obesity has made nonalcoholic fatty liver disease (NAFLD) the most common chronic liver disease. As a consequence, NAFLD and especially its inflammatory form nonalcoholic steatohepatitis (NASH) are the fastest increasing etiology of end-stage liver disease and hepatocellular carcinoma. Physical inactivity is related to the severity of fatty liver disease irrespective of body weight, supporting the hypothesis that increasing physical activity through exercise can improve fatty liver disease. This review summarizes the evidence for the effects of physical exercise on NAFLD and NASH. Several clinical trials have shown that both aerobic and resistance exercise reduce the hepatic fat content. From clinical and basic scientific studies, it is evident that exercise affects fatty liver disease through various pathways. Improved peripheral insulin resistance reduces the excess delivery of free fatty acids and glucose for free fatty acid synthesis to the liver. In the liver, exercise increases fatty acid oxidation, decreases fatty acid synthesis, and prevents mitochondrial and hepatocellular damage through a reduction of the release of damage-associated molecular patterns. In conclusion, physical exercise is a proven therapeutic strategy to improve fatty liver disease.

Association of the ideal cardiovascular behaviors and factors with the incidence of nonalcoholic fatty liver disease: a prospective study

OBJECTIVE

This study aimed to investigate the association of ideal cardiovascular behaviors and factors with the incidence of nonalcoholic fatty liver disease (NAFLD) prospectively.

PATIENTS AND METHODS

We analyzed 25 278 (21 433 men and 11 895 women) participants in the study. Participants were divided into four categories according to the number of ideal cardiovascular behaviors and factors: 0-2, 3, 4, and 5-7 groups. Multivariate logistic regression was used to calculate the odds ratios with 95% confidence intervals (CIs).

RESULTS

After adjustment for confounding factors, the multivariate logistic regression model showed that the risk of NAFLD among the groups with 3, 4, 5-7 ideal factors was lower than the 0-2 group; after adjustment for age, sex, income, education level, and other confounders, the odds ratios were 0.74 (95% CI: 0.68-0.80), 0.49 (95% CI: 0.45-0.53), and 0.37 (95% CI: 0.33-0.41), respectively.

CONCLUSION

The incidence of NAFLD decreased gradually with increasing ideal cardiovascular health behaviors and factors.

Effect of a short-term physical activity intervention on liver fat content in obese children

Nonalcoholic fatty liver disease is the most common chronic liver disease and can present with advanced fibrosis or nonalcoholic steatohepatitis. The purpose of this study was to investigate the effect of a 7-day intense physical activity intervention on liver fat content in children with obesity. Fifty-seven obese children (mean body mass index: 26.5 ± 3.2 kg/m²; mean age: 12.0 ± 0.8 years) participated in a 7-day physical activity program. All participants were housed together, and their food intake and energy expenditure were strictly controlled. Anthropometric measurements, abdominal computerized tomography scans, and blood analyses were conducted at baseline and post-intervention. Participants lost weight by 2.53 ± 0.85 kg on average (61.0 ± 9.8 vs. 58.5 ± 9.5 kg, p < 0.05), fat mass (16.7 ± 5.1 vs. 15.7 ± 4.9 kg, p < 0.05), and serum insulin (13.7 ± 6.7 vs. 3.5 ± 2.0 μU/mL, p < 0.05). However, liver fat content was increased, presented as liver-to-spleen ratio (LSR) where lower LSR represents higher liver fat content. The intervention increased aspartate transaminase level (29.42 ± 6.78 IU/L vs. 33.50 ± 9.60 IU/L, p < 0.001). The change in liver fat content was not associated with the change in fasting insulin and liver enzymes. Short-term intense physical activity increased liver fat content independent of change in fasting insulin level and liver enzymes. This is the first human study to report increased liver fat content after physical activity-induced rapid weight loss.

New trends on obesity and NAFLD in Asia

Traditionally, obesity and its related diseases have been considered a problem in Western countries. However, in the past two decades, urbanisation in many Asian countries has led to a sedentary lifestyle and overnutrition, setting the stage for the epidemic of obesity. This article reviews the epidemiological trend of obesity in Asia, with special emphasis on the emerging condition of non-alcoholic fatty liver disease (NAFLD). Currently, the population prevalence of NAFLD in Asia is around 25%, like many Western countries. While hepatocellular carcinoma and end-stage liver disease secondary to NAFLD remain uncommon, a rising trend has emerged. Around 8-19% of Asians with body mass indexes less than 25kg/m2 are also found to have NAFLD, a condition often described as "lean" or "non-obese" NAFLD. Although this condition is generally less severe than that in more obese patients, steatohepatitis and fibrotic disease are well recognized. Central adiposity, insulin resistance and weight gain are major risk factors, and genetic predisposition, such as the PNPLA3 polymorphism appears to be more important in the development of NAFLD in the non-obese population. Lifestyle modification remains the cornerstone of management for obesity and NAFLD, but few patients can achieve adequate weight reduction and even fewer can maintain the weight in the long run. While pharmacological agents have entered phase III development for steatohepatitis, Asian patients are under-represented in most drug trials. Future studies should define the optimal management of obesity and NAFLD in Asia.

Non-alcoholic Fatty Liver Disease in Lean Subjects: Characteristics and Implications

Non-alcoholic fatty liver disease (NAFLD) is commonly diagnosed in obese subjects; however, it is not rare among lean individuals. Given the absence of traditional risk factors, it tends to remain under-recognised. The metabolic profiles of lean NAFLD patients are frequently comparable to those of obese NAFLD patients. Though results from several studies have been mixed, it has been generally revealed that lean subjects with NAFLD have minor insulin resistance compared to that in obese NAFLD. Several genetic variants are associated with NAFLD without insulin resistance. Some data suggest that the prevalence of steatohepatitis and advanced fibrosis do not differ significantly between lean and obese NAFLD; however, the former tend to have less severe disease at presentation. The underlying pathophysiology of lean NAFLD may be quite different. Genetic predispositions, fructose- and cholesterol-rich diet, visceral adiposity and dyslipidaemia have potential roles in the pathogenic underpinnings. Lean NAFLD may pose a risk for metabolic disturbances, cardiovascular morbidity or overall mortality. Secondary causes of hepatic steatosis are also needed to be ruled out in lean subjects with NAFLD. The effectiveness of various treatment modalities, such as exercise and pharmacotherapy, on lean NAFLD is not known. Weight loss is expected to help lean NAFLD patients who have visceral obesity. Further investigation is needed for many aspects of lean NAFLD, including mechanistic pathogenesis, risk assessment, natural history and therapeutic approach.

Lifestyle predictors of obese and non-obese patients with nonalcoholic fatty liver disease: A cross-sectional study

BACKGROUND & AIMS

Most people with nonalcoholic fatty liver disease (NAFLD) are obese, and they usually eat more while being less physically active as compared to healthy individuals. However, little is known about the lifestyle patterns of non-obese or obese patients with NAFLD. The aim of this study was to investigate nutrition components and behavioral differences between non-obese and obese patients with NAFLD.

METHODS

This is a cross-sectional study comprising of 209 patients. Nutritional components and physical activity status were compared in obese and non-obese subjects with NAFLD against healthy controls. Dietary intake was assessed using the 5-day food diary. Physical activity was measured using the protocol of Korea Health and Nutrition Examination Survey. Total and regional body composition analysis was conducted using anthropometry and tetrapolar multi-frequency bio-impedance. Visceral adipose tissue, total abdominal adipose tissue, abdominal subcutaneous adipose tissue as well as liver fat were measured using abdomen tomography.

RESULTS

Non-obese subjects with NAFLD had higher levels of ALT, AST, GGT, triglyceride, fasting glucose; higher carbohydrate energy ratio; higher visceral fat area, subcutaneous area, body muscle mass, fat free mass and body fat compared to subjects without NAFLD. Subjects with obesity and NAFLD had higher ALT, AST, visceral fat, fasting glucose and HOMA-IR (homeostatic model assessment-insulin resistance), and less moderate-level physical activity compared to those with obesity who do not have NAFLD. Obese subjects with NAFLD also had higher blood pressure, visceral fat area, subcutaneous fat area, body fat, body fat percent and GGT compared to non-obese subjects with NAFLD. In multivariate analysis, carbohydrate energy ratio and physical activity less than moderate-level (<2 h/week) were predictors of NAFLD in non-obese subjects independent of the visceral fat, body muscle index, total energy intake, age and sex. Physical activity less than moderate-level was a predictor of NAFLD in obese subjects with NAFLD, independent of the HOMA-IR, visceral fat, total energy intake, fat energy percent, age and sex.

CONCLUSIONS

Percentage of carbohydrate intake percent and physical activity, less than moderate-level were independent predictors of NAFLD in non-obese subjects. Meanwhile, physical activity, less than moderate-level, was an independent predictor in obese subjects.

Fatty liver without a large "belly": Magnified review of non-alcoholic fatty liver disease in non-obese patients

Nonalcoholic fatty liver disease (NAFLD) is well described as a common cause of chronic liver disease, mostly in the obese population. It refers to a spectrum of chronic liver disease that starts with simple steatosis than progresses to nonalcoholic steatohepatitis and cirrhosis in patients without significant alcohol consumption. NAFLD in the non-obese population has been increasingly reported and studied recently. The pathogenesis of nonobese NAFLD is poorly understood and is related to genetic predisposition, most notably patatin-like phospholipase domain-containing 33 G allele polymorphism that leads to intrahepatic triglyceride accumulation and insulin resistance. Non-obese NAFLD is associated with components of metabolic syndrome and, especially, visceral obesity which seems to be an important etiological factor in this group. Dietary factors and, specifically, a high fructose diet seem to play a role. Cardiovascular events remain the main cause of mortality and morbidity in NAFLD, including in the non-obese population. There is not enough data regarding treatment in non-obese NAFLD patients, but similar to NAFLD in obese subjects, lifestyle changes that include dietary modification, physical activity, and weight loss remain the mainstay of treatment.

Nonobese Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) refers to a group of conditions characterized by hepatic steatosis in the absence of significant alcohol consumption. NAFLD is seen commonly in patients with metabolic abnormalities associated with obesity, such as type II diabetes, dyslipidemia, and metabolic syndrome. Evidently, however, not all obese subjects develop NAFLD and, more importantly, NAFLD can be found in nonobese individuals. Although NAFLD occurring in nonobese subjects has been reported in children and adults of all ethnicities, it appears to be recognized more frequently in Asians, even when strict ethnicity-specific body mass index criteria are used to define obesity. Studies based on liver biopsies suggest that the prevalence of nonalcoholic steatohepatitis and fibrosis does not differ significantly between nonobese NAFLD and NAFLD in obese patients. Visceral obesity as opposed to general obesity, high fructose and cholesterol intake, and genetic risk factors (eg, palatin-like phospholipase domain-containing 3) may be associated with nonobese NAFLD. In general, nonalcoholic steatohepatitis is associated with increased mortality, primarily from cardiovascular causes, independent of other metabolic factors. Although data regarding the mortality impact of nonobese NAFLD are not as mature, it may be important to identify high-risk nonobese NAFLD patients and manage their metabolic profile. Currently, lifestyle modification to reduce visceral adiposity, including dietary changes and physical activity, remains the standard of care in patients with nonobese NAFLD.

Transient remission of nonalcoholic fatty liver disease decreases the risk of incident type 2 diabetes mellitus in Japanese men

INTRODUCTION

It is unclear how the transient remission of nonalcoholic fatty liver disease (NAFLD) affects incident type 2 diabetes mellitus (T2DM). Here, we sought to determine the effect of the transient remission of NAFLD on incident T2DM in Japanese men.

MATERIALS AND METHODS

We used a population-based health check-up program. The primary outcome was set as incident T2DM. We divided the participants who showed NAFLD at the time of enrollment into three groups according to their clinical course of NAFLD: the Regression group, in which the participants showed a regression of NAFLD and no relapse during the follow-up period; the Transient Remission group, in which participants achieved a transient remission of NAFLD, but had a relapse of NAFLD; and the Persistent group, in which participants showed NAFLD throughout the follow-up. The Never group of participants who did not show NAFLD throughout the follow-up served as a reference.

RESULTS

The incidence rates of T2DM in the Never group, the Regression group, the Transient Remission group, and the Persistent group were 4.7% (62/1306), 9.2% (14/153), 18.0% (25/139), and 35.1% (120/342), respectively. In a multivariate Cox regression analysis with covariates, the adjusted hazard ratios for incident T2DM compared with the Never group were as follows: Regression group: 1.08 [95% confidence interval (CI) 0.53-2.04, P=0.81], Transient Remission group: 2.12 (95% CI 1.22-3.57, P<0.01), and Persistent group: 3.44 (95% CI 2.29-5.21, P<0.001). The adjusted hazard ratio of the Transient Remission group was significantly lower than that of the Persistent group (P<0.05).

CONCLUSION

Transient remission of NAFLD significantly decreased the risk of developing T2DM.

The chloroform extract of Cyclocarya paliurus attenuates high-fat diet induced non-alcoholic hepatic steatosis in Sprague Dawley rats

BACKGROUND

Hepatic steatosis (HS) is the early stage of nonalcoholic fatty liver disease which is caused by impaired hepatic lipid homeostasis. Cyclocarya paliurus, an herbal tea consumed in China, has been demonstrated to ameliorate abnormal lipid metabolism for the treatment of metabolic diseases.

PURPOSE

We aimed to investigate the regulative effect of chloroform extract from Cyclocarya paliurus (ChE) on treatment of HS, as well as key factors involved in hepatic lipid metabolism.

STUDY DESIGN

Sprague Dawley rats were fed with high-fat diet (HFD) for 6 weeks to induce HS and treated with or without ChE by gavage for 4 weeks.

METHODS

The body weight, relative liver weight and liver fat content were measured. Serum and liver total cholesterol, triglyceride and non-esterified fatty acids, as well as hepatic malonaldehyde levels were accessed by biochemical methods. Serum and liver TNF-α levels were quantified by ELISA kit. Histologic analysis and ¹H-MRS study were performed to evaluate HS level. RT-PCR and Western blot were also applied to observe the expression changes of key factors involved in hepatic lipid intake, synthesis, utilization and export.

RESULTS

ChE significantly decreased the rats' body weight, serum lipid and TNF-α level. ChE also reduced their relative liver weight, liver fat content, hepatic oxidative products and TNF-α level. Hepatic steatosis in HFD-fed rats was effectively regressed after 2-weeks administration of ChE. Moreover, ChE treatment remarkably reduced HFD-induced high expression level of fatty acid synthesis genes (including sterol-regulatory element-binding protein 1, acetyl-CoA carboxylase 1 and fatty acid synthase). However, it had no effect on mRNA expression of some genes involved in lipid uptake, β-oxidation and lipid outflow.

CONCLUSION

ChE exerted a promising regression effect on HS due to a reduced level of serum non-esterified fatty acids which might lead to a decrease in the amount of lipid taken in by the liver, as well as owing to the inhibition of hepatic lipid de novo synthesis to reduce liver lipid production.

Anti-inflammatory and antifatigue effect of Korean Red Ginseng in patients with nonalcoholic fatty liver disease

BACKGROUND

Korean Red Ginseng (KRG) is a well-known natural product with anticarcinogenic and antioxidant effects. We evaluated the antifatigue effect of KRG in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

Eighty patients with NAFLD were prospectively randomized to receive 3 wk of KRG or placebo in addition to counseling on healthy eating and regular exercise. Liver function test, proinflammatory cytokines, adiponectin, antioxidant activity, and fatigue score were measured and compared according to the body mass index between the KRG and placebo groups.

RESULTS

The liver function tests were significantly improved after 3 wk of treatment in both groups. The mean levels (at baseline and after treatment) of tumor necrosis factor-α were 108.0 pg/mL ± 54.8 pg/mL and 92.7 pg/mL ± 39.0 pg/mL (p = 0.018) in the KRG group and 123.1 pg/mL ± 42.1 pg/mL and 127.5 pg/mL ± 62.2 pg/mL (p = 0.694) in the placebo group, respectively. There was a significant difference in change of adiponectin levels between the KRG (7,751.2 pg/mL ± 3,108.1 pg/mL and 8,197.3 pg/mL ± 2,714.5 pg/mL) and placebo groups (7,711.6 pg/mL ± 3,041.3 pg/mL and 7,286.1 pg/mL ± 5,188.7 pg/mL, p = 0.027). In patients with overweight, the fatigue score was significantly decreased in the KRG group (35.0 ± 13.2 and 24.5 ± 8.9, p = 0.019).

CONCLUSION

Our results show that KRG might be effective in reducing proinflammatory cytokine and fatigue in overweight patients with NAFLD, in addition to improvements in adiponectin levels.

The impact of non-alcoholic fatty liver disease on incident type 2 diabetes mellitus in non-overweight individuals

BACKGROUND & AIMS

The aim of this study was to evaluate the impact of non-alcoholic fatty liver disease (NAFLD) on incident type 2 diabetes mellitus (T2DM) in non-overweight individuals with NAFLD.

METHODS

A population-based retrospective cohort study of 4629 participants who were enrolled in a health check-up programme for more than 10 years. A standardized questionnaire and abdominal ultrasonography were used to diagnose NAFLD. A cut-off point of BMI 23 kg/m(2) was used to define overweight (≥23.0 kg/m(2)) or non-overweight (<23.0 kg/m(2)). The primary outcome was incident T2DM.

RESULTS

Over a mean follow-up of 12.8 years, 351 participants (7.6%) developed T2DM. The incidence rate of T2DM was 3.2% in the non-overweight without NAFLD group, 14.4% in the non-overweight with NAFLD group, 8.0% in the overweight without NAFLD group and 26.4% in the overweight with NAFLD group. The adjusted hazard ratios for incident T2DM compared with the non-overweight without NAFLD group were as follows: 3.59 (95% CI: 2.14-5.76) in the non-overweight with NAFLD group, 1.99 (95% CI: 1.47-2.69) in the overweight without NAFLD group and 6.77 (95% CI: 5.17-8.91) in the overweight with NAFLD group. The adjusted hazard ratio in the non-overweight with NAFLD group was significantly higher than that in the overweight without NAFLD group or that in the non-overweight without NAFLD group.

CONCLUSIONS

Non-overweight individuals with NAFLD had a high risk of incident T2DM. Diagnosis of NAFLD is important in non-overweight individuals, and therefore it might be necessary to follow their health conditions on a long-term basis after detection of NAFLD.

Independent Association Between Improvement of Nonalcoholic Fatty Liver Disease and Reduced Incidence of Type 2 Diabetes

OBJECTIVE

Only a few studies have evaluated the long-term effects of nonalcoholic fatty liver disease (NAFLD) on type 2 diabetes mellitus (T2DM), and none have examined whether NAFLD improvement reduces T2DM incidence. We investigated the association between NAFLD improvement and T2DM incidence.

RESEARCH DESIGN AND METHODS

Between 2000 and 2012, 4,604 participants who underwent a health check twice with >10 years between were enrolled. Exclusion criteria were positive hepatitis B surface antigen, positive hepatitis C antibody, ethanol intake >20 g/day, and diabetes. The 3,074 eligible participants were divided into an NAFLD group (n = 728) and a non-NAFLD group (n = 2,346) according to ultrasonography-detected fatty liver. The NAFLD group was categorized into an improved group (n = 110) and a sustained NAFLD group (n = 618) based on fatty liver disappearance at the second visit. Incident T2DM odds ratios (ORs) were estimated by logistic regression models adjusted for age, sex, BMI, impaired fasting glucose, family history of diabetes, dyslipidemia, hypertension, and physical exercise.

RESULTS

T2DM occurred in 117 participants (16.1%) in the NAFLD group and 72 (3.1%) in the non-NAFLD group. NAFLD at baseline was associated with T2DM incidence (multivariate OR 2.37 [95% CI 1.60-3.52]). T2DM occurred in 7 participants (6.4%) in the improved group and in 110 (17.8%) in the sustained NAFLD group. NAFLD improvement was associated with reduced T2DM incidence (multivariate OR 0.27 [95% CI 0.12-0.61]).

CONCLUSIONS

NAFLD improvement is associated with T2DM incidence reduction.

Exercise improves adipose function and inflammation and ameliorates fatty liver disease in obese diabetic mice

OBJECTIVE

Adipose inflammation and dysfunction underlie metabolic obesity. Exercise improves glycemic control and metabolic indices, but effects on adipose function and inflammation are less clear. Accordingly, it was hypothesized that exercise improves adipose morphometry to reduce adipose inflammation in hyperphagic obese mice.

METHODS

Alms1 mutant foz/foz mice housed in pairs were fed an atherogenic or chow diet; half the cages were fitted with a computer-monitored wheel for voluntary exercise. Insulin-induced AKT-phosphorylation, adipocyte size distribution, and inflammatory recruitment were studied in visceral versus subcutaneous depots, and severity of fatty liver disease was determined.

RESULTS

Exercise prevented obesity and diabetes development in chow-fed foz/foz mice and delayed their onset in atherogenic-fed counterparts. Insulin-stimulated phospho-AKT levels in muscle were improved with exercise, but not in adipose or liver. Exercise suppressed adipose inflammatory recruitment, particularly in visceral adipose, associated with an increased number of small adipocyte subpopulations, and enhanced expression of beige adipocyte factor PRDM16 in subcutaneous fat. In atherogenic-fed foz/foz mice liver, exercise suppressed development of nonalcoholic steatohepatitis and related liver fibrosis.

CONCLUSIONS

Exercise confers metabo-protective effects in atherogenic-fed hyperphagic mice by preventing early onset of obesity and diabetes in association with enhanced muscle insulin sensitivity, improved adipose morphometry, and suppressed adipose and liver inflammation.

Physical activity as a treatment of non-alcoholic fatty liver disease: A systematic review

AIM

To review the effectiveness of exercise as a therapy for nonalcoholic fatty liver disease (NAFLD) and potential benefits in treating insulin resistance and atherosclerosis.

METHODS

Medline (EBSCOhost) and PubMed were searched for English-language randomized controlled trials and prospective cohort studies in human adults aged ≥ 18 which investigated the various effects of exercise alone, a combination of exercise and diet, or exercise and diet coupled with behavioral modification on NAFLD from 2010 to Feburary 2015.

RESULTS

Eighteen of 2298 available studies were chosen for critical review, which included 6925 patients. Nine (50%) studies were randomized controlled trials. Five (27.8%) studies utilized biopsy to examine the effects of physical activity on hepatic histology. The most commonly employed imaging modality to determine change in hepatic steatosis was hydrogen-magnetic resonance spectroscopy. Only two studies examined the effects of low impact physical activity for patients with significant mobility limitations and one compared the efficacy of aerobic and resistance exercise. No studies examined the exact duration of exercise required for hepatic and metabolic improvement in NAFLD.

CONCLUSION

While exercise improved hepatic steatosis and underlying metabolic abnormalities in NAFLD, more studies are needed to define the most beneficial form and duration of exercise treatment.

Quantified Risk Assessment for Major Hepatectomy via the Indocyanine Green Clearance Rate and Liver Volumetry Combined with Standard Liver Volume

BACKGROUND

Preoperative risk assessment for post-hepatectomy liver failure (PHLF) is essential for major hepatectomy. We intended to establish a standard liver volume (SLV) formula for Korean patients and validate the predictive power of the indocyanine green clearance rate constant (ICG-K) fraction of future remnant liver (FRL) (FRL-kICG) to total liver volume (TLV).

METHODS

This study comprised 2 retrospective studies. Part I established SLV formula and acquired ICG pharmacokinetic data from 2155 living donors. In part II, FRL-kICG cutoff was determined using 723 patients who underwent right liver resection for hepatocellular carcinoma.

RESULTS

In part I, the formula SLV (mL) = -456.3 + 969.8 × BSA (m(2)) (r = 0.707, r (2) = 0.500, p = 0.000) was derived with mean volume error of 10.5%. There was no correlation between TLV and ICG retention rate at 15 min. With a cutoff of 0.04 with hepatic parenchymal resection rate (PHRR) limit of 70%, 99.0% of our living donors were permissible for left or right hepatectomy. In part II, 25 hepatocellular carcinoma patients (3.5%) showed an FRL-kICG or SLV-corrected FRL-kICG <0.05. Of these, 4 (16 %) died of PHLF, whereas only 2 (0.3%) died in the other patient group with both an FRL-kICG and SLV-corrected FRL-kICG ≥ 0.05 (P = 0.000).

CONCLUSIONS

The FRL-kICG appears to reliably predict PHLF risk quantitatively. We suggest FRL-kICG cutoffs of 0.04 and 0.05 with PHRR limits of 70% and 65% for normal and diseased livers, respectively. Further validation with large patient population in multicenter studies is necessary to improve FRL-kICG predictability.

Racial and ethnic disparities in access to and utilization of living donor liver transplants

Living donor liver transplantation (LDLT) is a comparable alternative to deceased donor liver transplantation and can mitigate the risk of dying while waiting for transplant. Although evidence exists of decreased utilization of living donor kidney transplants among racial minorities, little is known about access to LDLT among racial/ethnic minorities. We used Organ Procurement and Transplantation Network/United Network for Organ Sharing data from February 27, 2002 to June 4, 2014 from all adult liver transplant recipients at LDLT-capable transplant centers to evaluate differential utilization of LDLTs based on race/ethnicity. We then used data from 2 major urban transplant centers to analyze donor inquiries and donor rule-outs based on racial/ethnic determination. Nationally, of 35,401 total liver transplant recipients performed at a LDLT-performing transplant center, 2171 (6.1%) received a LDLT. In multivariate generalized estimating equation models, racial/ethnic minorities were significantly less likely to receive LDLTs when compared to white patients. For cholestatic liver disease, the odds ratios of receiving LDLT based on racial/ethnic group for African American, Hispanic, and Asian patients compared to white patients were 0.35 (95% CI, 0.20-0.60), 0.58 (95% CI, 0.34-0.99), and 0.11 (95% CI, 0.02-0.55), respectively. For noncholestatic liver disease, the odds ratios by racial/ethnic group were 0.53 (95% CI, 0.40-0.71), 0.78 (95% CI, 0.64-0.94), and 0.45 (95% CI, 0.33-0.60) respectively. Transplant center-specific data demonstrated that African American patients received fewer per-patient donation inquiries than white patients, whereas fewer African American potential donors were ruled out for obesity. In conclusion, racial/ethnic minorities receive a disproportionately low percentage of LDLTs, due in part to fewer initial inquiries by potential donors. This represents a major inequality in access to a vital health care resource and demands outreach to both patients and potential donors.

Rapid Reversal of Liver Steatosis With Life Style Modification in Highly Motivated Liver Donors

BACKGROUND

Liver steatosis is the leading cause of donor rejection in living donor liver transplantation. Rapid weight loss is difficult to achieve in a short period of time, moreover it has been thought to worsen liver histology.

METHODS

Donors who had significant steatosis based on liver biopsy were recommended 1200 Kcal/day and a minimum of 60 min/day moderate cardio training. Two patients were advised statins for dyslipidemia. None of the donors had metabolic syndrome. A second ultrasound guided liver biopsy was done at 28 ± 10 days. Donors with nonalcoholic steatohepatitis/fibrosis or >30% steatosis were not included.

RESULTS

From July 2010 to January 2015, 16 donors were advised aggressive life style modification after initial biopsy; 15 (10 males, age 27.5 ± 6.5 years, baseline body mass index 28.4 ± 2.1 Kg/M(2)) successfully reduced weight and 14 underwent donation after favorable second biopsy. Mean weight loss was 7 ± 4.3 kg (8.4 ± 4.6%). Second liver biopsy was done at 28 ± 10 days, there was decrease in steatosis in all but one including normalization of liver biopsy in 7 donors. Three donors had mild inflammation on first biopsy and they had improvement in second biopsy. All the donors and their recipients had an uneventful post-operative course.

CONCLUSION

Steatosis can be reversed in a short duration by aggressive life style modifications in highly motivated liver donors.

Switching bipolar hepatic radiofrequency ablation using internally cooled wet electrodes: comparison with consecutive monopolar and switching monopolar modes

OBJECTIVE

To evaluate whether switching bipolar radiofrequency ablation (SB-RFA) using three internally cooled wet (ICW) electrodes can induce coagulations >5 cm in porcine livers with better efficiency than consecutive monopolar (CM) or switching monopolar (SM) modes.

METHODS

A total of 60 coagulations were made in 15 in vivo porcine livers using three 17-gauge ICW electrodes and a multichannel radiofrequency (RF) generator. RF energy (approximately 200 W) was applied in CM mode (Group A, n = 20) for 24 min, SM mode for 12 min (Group B, n = 20) or switching bipolar (SB) mode for 12 min (Group C, n = 20) in in vivo porcine livers. Thereafter, the delivered RFA energy, as well as the shape and dimension of coagulations were compared among the groups.

RESULTS

Spherical- or oval-shaped ablations were created in 30% (6/20), 85% (17/20) and 90% (18/20) of coagulations in the CM, SM and SB groups, respectively (p = 0.003). SB-RFA created ablations >5 cm in minimum diameter (Dmin) in 65% (13/20) of porcine livers, whereas SM- or CM-RFA created ablations >5 cm in only 25% (5/20) and 20% (4/20) of porcine livers, respectively (p = 0.03). The mean Dmin of coagulations was significantly larger in Group C than in Groups A and B (5.1 ± 0.9, 3.9 ± 1.2 and 4.4 ± 1.0 cm, respectively, p = 0.002) at a lower delivered RF energy level (76.8 ± 14.3, 120.9 ± 24.5 and 114.2 ± 18.3 kJ, respectively, p < 0.001).

CONCLUSION

SB-RFA using three ICW electrodes can create coagulations >5 cm in diameter with better efficiency than do SM- or CM-RFA.

ADVANCES IN KNOWLEDGE

SB-RFA can create large, regular ablation zones with better time-energy efficiency than do CM- or SM-RFA.

Combined Use of MR Fat Quantification and MR Elastography in Living Liver Donors: Can It Reduce the Need for Preoperative Liver Biopsy?

PURPOSE

To evaluate the diagnostic performance of magnetic resonance (MR) fat quantification and MR elastography for the assessment of hepatic steatosis and fibrosis in living liver donor candidates.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, and the requirement of informed consent was waived. Donors who underwent MR fat quantification and MR elastography at 1.5 T, followed by liver biopsy, were chronologically grouped into test and validation groups. In the test group (n = 362), MR fat fraction and liver stiffness were compared among donors with normal parenchyma (n = 244), simple steatosis (n = 71), steatosis with inflammatory activity (n = 21), nonalcoholic steatohepatitis (n = 17), and fibrosis (n = 9). Diagnostic performance of the two techniques was assessed by using receiver operating characteristic curve analysis for the detection of substantial steatosis (macrovesicular fat ≥ 10%) or fibrosis (≥F1) and was tested in a validation group (n = 34).

RESULTS

In the test group, donors with steatosis showed significantly higher fat fraction than donors without steatosis (P < .0001), and donors with fibrosis and nonalcoholic steatohepatitis showed significantly higher liver stiffness values than donors without fibrosis (P < .0001). Areas under the curve were 0.93 (cutoff value > 5.8%) for MR fat quantification and 0.85 (cutoff value > 1.94 kPa) for MR elastography. By using those values, the combination of the two techniques could be used to detect substantial steatosis or fibrosis with 100% sensitivity (12 of 12 patients, 95% confidence interval: 73.4%, 100%) and 100% negative predictive value (15 of 15 patients, 95% confidence interval: 78.0%, 100%) in the validation group.

CONCLUSION

A combination of MR fat quantification and MR elastography can provide sufficient sensitivity to detect substantial steatosis or fibrosis (≥F1) in liver donor candidates.

Relation of physical activity to prevalence of nonalcoholic Fatty liver disease independent of cardiometabolic risk

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity and insulin resistance and has been linked with increased cardiovascular risk. Although physical activity (PA) and lifestyle modification are often recommended in patients at cardiovascular risk, the benefit across the cardiometabolic risk spectrum is unclear. We aimed to evaluate the relation of PA and NAFLD independent of metabolic syndrome (MS) or obesity. We evaluated 5,743 healthy Brazilian subjects (43 ± 10 years, 79% men) without clinical coronary heart disease from December 2008 to December 2010. NAFLD was diagnosed using ultrasounds, and self-reported PA was assessed using the International Physical Activity Questionnaire scale. In a multivariate logistic regression adjusted for cardiometabolic risk factors, we evaluated for an independent association of NAFLD and PA. In the total study population, NAFLD prevalence was 36% (n = 2,075), obesity 23% (1,300), and MS 20% (1,152). NAFLD was more prevalent in subjects with MS (74%) than those without (26%) and in those obese (73%) than in those nonobese (25%). Overall, 1,305 (23%) subjects reported low activity, 1,990 (35%) moderate activity, and 2,448 (42%) high activity. NAFLD prevalence was lower at higher levels of reported PA (low 45%, moderate 38%, and high 30%, p <0.001). After adjusting for risk factors, subjects with high activity had lower odds of having NAFLD. The favorable association was independent of obesity or MS. In conclusion, PA presents a dose-response association with NAFLD independent of the MS or obesity. Our results are compatible with the idea that benefits of PA are relevant to everyone regardless of cardiometabolic risk.

Prevalence analysis of de novo hepatic steatosis following pylorus-preserving pancreaticoduodenectomy

BACKGROUND

Prevalence of hepatic steatosis following pylorus-preserving pancreaticoduodenectomy (PPPD) is high. This study intended to reveal the prevalence and patterns of de novo hepatic steatosis following PPPD.

METHODS

We investigated postoperative de novo hepatic steatosis following PPPD (n = 101) with a control group of bile duct resection (BDR) (n = 54).

RESULTS

At postoperative 1 year, hepatic steatosis occurred in 21 of 82 patients (25.6%) of PPPD group and in 2 of 47 patients (4.3%) of BDR group (p = 0.001). Thereafter, at 2 to 5 years, a high prevalence of hepatic steatosis persisted in the PPPD group, but no further occurrence developed in BDR group. Once steatosis developed, it persisted until the end of the study period or patient death. Five-year cumulative incidence of hepatic steatosis was 26.7% in the PPPD group and 3.7% in BDR group (p < 0.001). Univariate analyses showed that patient sex, age, body mass index, blood lipid profile, recurrence of tumor, and diabetes did not have significant influence on the development of hepatic steatosis following PPPD.

CONCLUSIONS

De novo hepatic steatosis may develop in a not negligible proportion of patients undergone PPPD. Multicenter studies with a high number of patients are needed to elucidate its pathogenesis and to find effective treatment for pancreaticoduodenectomy-associated hepatic steatosis.

The impact of weight changes on nonalcoholic Fatty liver disease in adult men with normal weight

BACKGROUND

Although it is known that losing weight has an effect on the treatment of non-alcoholic fatty liver disease, the studies that show how losing weight affects the non-alcoholic fatty liver disease for the normal weight male adults are limited so far. In this study, we set body mass index as criteria and investigated how the weight changes for 4 years makes an impact on the risk of non-alcoholic fatty liver disease for the male adults who have the normal body mass index.

METHODS

From January to December of 2004, among the normal weight male adults who had general check-up at the Health Promotion Center of Ulsan University Hospital, 180 people (average age, 47.4 ± 4.61 years) who were diagnosed with fatty liver through abdominal ultrasonography were included in this study and were observed according to the variety of data and ultrasonography after 4 years (2008). People who had a history of drinking more than 140 g of alcohol per week or who had a past medical history were excluded from the analysis. The weight change of subjects was calculated using the formula 'weight change = weight of 2008 (kg) - weight of 2004 (kg)' and classified into three groups, loss group (≤-3.0 kg), stable group (-2.9 to 2.9 kg), and gain group (≥3.0 kg). The odds for disappearance of non-alcoholic fatty liver disease in those three different groups were compared.

RESULTS

Among 180 subjects, compared with stable group (67.2%, 121 subjects), loss group (11.7%, 21 subjects) showed 18.37-fold increase in the odds of disappearance of non-alcoholic fatty liver disease (95% confidence interval [CI], 4.34 to 77.80) and gain group (21.1%, 38 subjects) showed 0.28-fold decrease in the odds of disappearance of non-alcoholic fatty liver disease (95% CI, 0.10 to 0.83).

CONCLUSION

Even for the normal weight people, losing weight has an effect on the improvement of non-alcoholic fatty liver disease.

Therapeutic role of niacin in the prevention and regression of hepatic steatosis in rat model of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), a leading cause of liver damage, comprises a spectrum of liver abnormalities including the early fat deposition in the liver (hepatic steatosis) and advanced nonalcoholic steatohepatitis. Niacin decreases plasma triglycerides, but its effect on hepatic steatosis is elusive. To examine the effect of niacin on steatosis, rats were fed either a rodent normal chow, chow containing high fat (HF), or HF containing 0.5% or 1.0% niacin in the diet for 4 wk. For regression studies, rats were first fed the HF diet for 6 wk to induce hepatic steatosis and were then treated with niacin (0.5% in the diet) while on the HF diet for 6 wk. The findings indicated that inclusion of niacin at 0.5% and 1.0% doses in the HF diet significantly decreased liver fat content, liver weight, hepatic oxidative products, and prevented hepatic steatosis. Niacin treatment to rats with preexisting hepatic steatosis induced by the HF diet significantly regressed steatosis. Niacin had no effect on the mRNA expression of fatty acid synthesis or oxidation genes (including sterol-regulatory element-binding protein 1, acetyl-CoA carboxylase 1, fatty acid synthase, and carnitine palmitoyltransferase 1) but significantly inhibited mRNA levels, protein expression, and activity of diacylglycerol acyltrasferase 2, a key enzyme in triglyceride synthesis. These novel findings suggest that niacin effectively prevents and causes the regression of experimental hepatic steatosis. Approved niacin formulation(s) for other indications or niacin analogs may offer a very cost-effective opportunity for the clinical development of niacin for treating NAFLD and fatty liver disease.

Lifestyle interventions for the treatment of non-alcoholic fatty liver disease

The burden of non-alcoholic fatty liver disease (NAFLD) worldwide is a significant clinical and public health issue, affecting approximately one third of the Western population. This review assesses the effect and impact lifestyle interventions have on the treatment of this common condition. We review studies comparing the effect of calorie restriction and exercise programs, as well as comparison of lifestyle intervention with pharmaceutical intervention. Both calorie restriction and exercise programs are shown to be beneficial in improving features of metabolic syndrome and surrogate markers of NAFLD. The paucity of studies using histological improvement hinders the ability to conclude a benefit on improvement of histological NAFLD, although this is shown in a small number of studies. There is a need to extend the intervention period to show a sustained improvement with intervention as most studies have a follow up period of 12 months of less.

NAFLD in Asia--as common and important as in the West

NAFLD--regarded as a consequence of the modern sedentary, food-abundant lifestyle prevalent in the West--was recorded in Japan nearly 50 years ago and its changing epidemiology during the past three decades is well-documented. NAFLD, and its pathologically more severe form NASH, occur in genetically susceptible people who are over-nourished. Asian people are particularly susceptible, partly owing to body composition differences in fat and muscle. Community prevalence ranges between 20% (China), 27% (Hong Kong), and 15-45% (South Asia, South-East Asia, Korea, Japan and Taiwan). This Review presents emerging data on genetic polymorphisms that predispose Asian people to NAFLD, NASH and cirrhosis, and discusses the clinical and pathological outcomes of these disorders. NAFLD is unlikely to be less severe in Asians than in other populations, but the associated obesity and diabetes pandemics have occurred more recently in Asia than in Europe and the USA, and occur with reduced degrees of adiposity. Cases of cryptogenic cirrhosis and hepatocellular carcinoma have also been attributed to NAFLD. Public health efforts to curb over-nutrition and insulin resistance are needed to prevent and/or reverse NAFLD, as well as its adverse health outcomes of type 2 diabetes, cardiovascular events, cirrhosis and liver cancer.